1. Field of the Invention
The present invention relates generally to medical devices and, more particularly, to injection apparatus that facilitate and improve the ability to pass viscous materials through lumens of small aperture.
2. Description of Related Art
The term xe2x80x9cstress urinary incontinencexe2x80x9d refers to a functionally insufficient urinary tract of a patient. In a patient having this condition, the tissue relaxation of the sphincter mechanism, located at the urinary outflow of the bladder into the urethra, can cause a loss of bladder control. Cystoscopes are typically used to study the urethra and bladder and to evaluate, for example, a patient""s urinary incontinence condition. A typical cystoscope may comprise a tubular instrument equipped with, for example, a visual channel and a working channel, and constructed to be inserted through the urethra for viewing of the urethra and bladder.
Treatment of a urinary incontinence condition may comprise the injection of a filler material, such as collagen, into and adjacent to the urinary sphincter muscle at the bladder neck, to thereby bulk up the tissue and assist in the adequate closure of the urinary sphincter.
Acid reflux is a digestive disorder which similarly involves the tissue relaxation of a sphincter mechanism. In the case of acid reflux, which is commonly known as gastroesophageal reflux disease (GERD) or heartburn, the lower esophageal sphincter connecting the esophagus to the stomach begins to malfunction.
During proper operation of the lower esophageal sphincter, the lower esophageal sphincter opens to allow food to pass into the stomach and closes to prevent food and acidic stomach fluids from flowing back up into the esophagus. Gastroesophageal reflux occurs when the lower esophageal sphincter is weak or relaxes inappropriately, allowing the stomach""s contents to retrograde or flow up into the esophagus.
This retrograde flow of gastric contents back into the esophagus, through what should be a one-way valve into the stomach, can damage the esophagus. More particularly, the contents of the stomach are very acidic; and the lining of the stomach is specially designed to cope with the lower pH contents. The esophagus, on the other hand, is not suited for such exposure to highly acidic materials. Thus, when acid retrogrades from the stomach into the esophageal tissues, irritation and inflammation will often result to these tissues.
The severity of tissue damage which can result from gastroesophageal reflux disease can depend on factors such as the dysfunctional level of the lower esophageal sphincter, the type and amount of fluid brought up from the stomach, and the neutralizing effect of the patient""s saliva.
Another factor, which may affect the severity of a particular gastroesophageal reflux disorder, is the patient""s esophageal motility. Lack of esophageal motility can occur through either of two mechanisms. When incomplete emptying of the esophagus into the stomach after ingestion of liquids or solids occurs, the motility of the esophagus can be said to be affected, resulting in esophageal reflux. Also, esophageal reflux can occur when small amounts of gastric contents, which may be refluxed into the lower esophagus, are not rapidly emptied back into the stomach. Delays in the emptying of this material, caused by an esophageal motility disorder, for example, can lead to irritation of the esophageal mucosa and possibly to the sensation of heartburn or the development of esophagitis.
Various tools and instruments have been used in the prior art for the treatment of urinary incontinence and acid reflux disease. Gastroscopes are typically used to study the esophagus and to evaluate, for example, a patient""s acid reflux condition. A gastroscope typically comprises a flexible, lighted instrument that is inserted through the mouth and esophagus to view the stomach. Similarly, a cystoscope is typically inserted through a patient""s urethra to facilitate evaluation of, for example, a urinary incontinence condition.
Treatment of either of the above-mentioned disorders may include one or more injections of a viscous material, such as collagen, into the vicinity of either the lower esophageal sphincter (for treating acid reflux) or the sphincter of the urethra (for treating urinary incontinence). These injection procedures typically involve elongate catheters for the delivery of viscous materials through the body passages and to the target sites of injection. The force required to deliver a viscous material through the delivery lumen of an elongate catheter will naturally increase as the length of the elongate catheter increases. Moreover, the types of elongate catheters used with these surgical procedures will typically have delivery lumens of relatively small cross-sectional areas, thus further augmenting the force required to deliver the viscous material through the length of the elongate catheter.
To compensate for the greater required force, it would be desirable to form the elongate catheter to have a lumen with a relatively large cross-sectional area to facilitate flow of the viscous material therethrough. Another design criterion is that the diameter of the needle tip should be relatively small to reduce tissue trauma at the injection site, to increase precision in some instances, and to reduce patient discomfort.
In order to meet the objectives of both a relatively large delivery lumen and a relatively small needle tip, a juncture must be formed at some point along the length of the needle to transition the needle diameter from a relatively large size to a relatively small size. If the transition point is abrupt or too great in magnitude, optimal flow of the viscous material through the needle may be inhibited.
An injection apparatus, as disclosed herein, may comprise a transition-bore needle apparatus to optimize the flow of viscous material from the injection apparatus. An injection apparatus, as disclosed herein, may comprise a hand-held injection facilitation apparatus which reduces the effort required to displace viscous material from the injection apparatus. The hand-held injection facilitation apparatus is structured to cooperatively interact with a syringe to cause displacement of viscous material from the syringe. An injection apparatus may comprise a combination of a transition-bore needle apparatus, and a hand-held injection facilitation apparatus, disclosed herein.
A transition-bore needle apparatus is provided to optimize the flow of a viscous material through a decreasing-diameter lumen of a needle. The transition-bore needle apparatus comprises a proximal end and a distal end, and the lumen extends from the proximal end of the transition-bore needle apparatus to the distal end of the transition-bore needle apparatus. A diameter at a proximal portion of the transition-bore needle apparatus is greater than a diameter at a distal portion of the transition-bore needle apparatus.
In accordance with one aspect of the present invention, the proximal portion of the transition-bore needle apparatus comprises a first needle having a first diameter, and the distal portion of the transition-bore needle apparatus comprises a second needle having a second diameter. The first diameter is greater than the second diameter. The first needle comprises a proximal end, a distal end, and a first lumen extending through the first needle from the proximal end to the distal end, and the second needle similarly comprises a proximal end, a distal end, and a second lumen extending through the second needle from the proximal end of the second needle to the distal end of the second needle.
The lumen of the transition-bore needle apparatus comprises both a portion of the first lumen of the first needle and a portion of the second lumen of the second needle. A juncture thus exists within the lumen of the transition-bore needle apparatus, where the diameter thereof transitions from the first diameter to the second diameter. At this juncture, the proximal end of the first needle terminates within the second lumen. In accordance with an aspect of the present invention, the proximal end of the first needle is beveled to improve a flow of viscous material through the lumen of the transition-bore needle apparatus. In accordance with another aspect of the present invention, the proximal end of the first needle is chamfered to improve a flow of viscous material through the lumen of the transition-bore needle apparatus. According to yet another aspect of the present invention, the proximal end of the first needle is both chamfered and beveled to improve a flow of viscous material through the lumen of the transition-bore needle apparatus.
The transition-bore needle apparatus of the facilitates the injection of viscous filler material by optimizing a flow of the viscous material through the lumen of the transition-bore needle apparatus. The transition-bore needle apparatus may be used in conjunction with surgical instruments, such as endoscopes, cystoscopes, and gastroscopes, to aid in intraluminal injections of materials into body tissues within body lumens. When the body lumen comprises an esophagus, the gastroscope is inserted through the esophagus into a vicinity of the lower esophageal sphincter, and a long needle is used to inject a filler material into and adjacent to the lower esophageal sphincter tissues for the treatment of acid reflux. When the body lumen comprises a female urethra, the cystoscope is inserted through the urethra to the urinary sphincter adjacent to the bladder neck, and a long needle is used to inject a filler material into and adjacent to the urinary sphincter tissues for the treatment of stress urinary incontinence. The filler material may also be injected, for example, along a greater length of the urethra.
The injection apparatus disclosed herein thus facilitates the injection of viscous filler materials, and may provide for increased speed, accuracy and efficiency in dispensing such materials. The injection of bulking agents into the respective tissues of body sphincters helps fortify the respective tissue structures and re-establish normal sphincter control. The transition-bore needle apparatus of the injection apparatus and associated methods of operation disclosed herein may be configured for and used on other body passages and tissues (e.g., wrinkles) as well in modified embodiments.
An injection apparatus may comprise a hand-held injection facilitation apparatus to increase the precision of dispensing of a material from a syringe. The injection facilitation apparatus may be used in conjunction with surgical instruments, such as endoscopes, cystoscopes, and gastroscopes, to aid in transurethral injection for intraluminal injections of materials into body tissues, and to visualize tissue within a body lumen. When the body lumen comprises an esophagus, the gastroscope is inserted through the esophagus into a vicinity of the lower esophageal sphincter, and a long needle is used to inject a filler material into and adjacent to the lower esophageal sphincter tissues for the treatment of acid reflux. When the body lumen comprises a female urethra, the gastro cystoscope is inserted through the urethra into the urinary sphincter adjacent to the bladder neck, and a long needle is used to inject a filler material into and adjacent to the urinary sphincter muscle tissues for the treatment of stress urinary incontinence. The filler material may also be injected, for example, along the entire length of the urethra.
The hand-held injection facilitation apparatus of the injection apparatus facilitates the injection of the viscous filler materials, and provides for increased accuracy in dispensing such materials. The injection of a urinary bulking agents into the respective tissues of body sphincters helps fortify the respective tissue structures and re-establish normal bladder sphincter control. The apparatus of the present invention and associated methods of operation disclosed herein may be configured for and used on other body passages as well in modified embodiments.
In accordance with one aspect of the present invention, an injection facilitation apparatus is constructed for use in conjunction with a stainless steel needle tip catheter that can be introduced into a patient""s urethra or esophagus in a treatment for urinary incontinence or gastro-esophageal reflux. The treatment for gastro-esophageal reflux disease may be fashioned to increase the strength or the length of the lower esophageal sphincter (LES) by depositing a viscous material around the lower esophageal sphincter. The suspension can be injected via a syringe and needle directly into the specific areas where the viscous agent is desired. A principal use of the exemplary embodiment is to accurately dispense the viscous material to thereby alter the physiological architecture of the patient""s sphincter and adjacent tissues. Thus the bio-mechanical characteristics of the sphincter and surrounding tissues are altered to alleviate urinary incontinence and gastro-esophageal reflux.
The subjects and objects of this disclosure relate to novel methods and instruments for facilitating the controlled dispensing of viscous material in the interior of the body, including but not limited to soft tissues, and lumen structures (e.g., esophagus, urethra).
The present invention, together with additional features and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying illustrative drawings.